Age-based seizure threshold determination

The intent was to improve seizure threshold titration by decreasing stimuli number.

An age-based method of titration for initial seizure threshold bilateral electroconvulsive therapy was constructed and used in 15 women and 9 men aged 35 to 80 years. Titration steps were one eighth, one fourth, three eighths, one half, five eighths, three fourths, 1, and 1.2 times age, expressed as "% Energy."

Male thresholds were a significantly (P < 0.05, t(22) = 2.18) higher percentage of age (61.9%; SD, 32.6%) than female thresholds (41.2%; SD, 15.2%). Four women (27%) and 4 men (44%) showed seizure thresholds more than 50% of age. On average, women received 3.2 stimuli and men received 4.4 stimuli. No patient seized at one-eighth age. All patients who seized at one-fourth age were women and younger than 65 years.

For women younger than 65 years, these data suggest that titration starting at one-fourth age should require 1.8 stimuli on average. For older women, starting at three-eighths age should average 1.8 stimuli. For men, starting at three-eighths age should require 2.4 stimuli, but with steps at three fourths, 1, and 1.25 age titration should average 1.8 stimuli. Age-based dosing should succeed in women younger than 65 years at one-half age and older than 65 years at five-eighths age. For men, dosing at one-half age should succeed among one half and is a reasonable initial titration dose.